It's claimed commuters using the Thameslink rail line which runs from Bedford to London may have to wait longer for improved services.
While changes have been made, including longer trains and the current redevelopment of Blackfriars and London Bridge stations, the National Audit Office is concerned progress is too slow.
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Some morning brightness on Boxing Day but cloud increasing, with rain, sleet and snow, spreading in late afternoon. Turning windy.
Starting cold and dry Boxing Day. Wet and windy later.
The Met Office has issued a yellow weather warning for the risk of rain turning to snow later on Boxing Day in parts of the Anglia region